Racheting/ non racheting gears and dogs.

**OnPad** · 02-24-2024, 06:56 PM

I get that. You had me a little conflusterd in sentence 2 on post 10.
I dont see a problem with only running half the ramp by swapping the dog, and whatever other parts to make the dog spring loaded in the correct way. I'll leave you alone now. Maybe someone that has done this will chime in.

**LakeFever** · 02-24-2024, 07:15 PM

NZ did you source Mercury lower unit tools to do this or make your own? Especially with regards to pinion depth

**NZ Sidewinder** · 02-24-2024, 07:31 PM

LOL
Yeah Mate.
Well not totally all from Merc.
My base trade is Fitting Turning and Machining.
So I made my pinion height tool and deep cone puller, drive shaft pre load is just a valve spring, backlash is dine with common mag base dti on heavy steel block.
Pinion bearing tools are really simple pullers and drifts
Carrier needle roller is push out is a perfect size 1/2 inch drive flat back socket with the long extension fitted from the front not the back.
Small hydraulic press,
Large cover nut castle spanner, shift shaft spanner and top dridrive shaft bearing nut spanner all from Mercury
Forward bearing conedrift is home made and I always use a heat gun to fit that bearing cone..
8 spline nut from Mercury also.

Carrier puller from Mercury waste of time on Salties
A heavy duty puller that pulls off the face of the boxbis required.

**racervboat** · 02-28-2024, 11:21 AM

All i know is you can put ratcheting gear set guts including the propshaft and dog into a non ratchet case or vice versa

**LakeFever** · 02-28-2024, 12:23 PM

Originally Posted by racervboat

All i know is you can put ratcheting gear set guts including the propshaft and dog into a non ratchet case or vice versa

Helpful info thanks for sharing

**OnPad** · 02-28-2024, 01:17 PM

From the research I've done these lu's have a big front bearing and all ratchet, c1, c, and the older preload driveshaft lu's..... The newer non ratchet lu's have a small bearing with a c2, c3, and c4 in the part number.
This info is just hearsay, as I haven't had all these apart and measured. Anyone that has info otherwise is encouraged to share their knowledge.
I suppose alot is possible with the right combination of parts, shims, and machine work.
Some more hearsay for anyone interested....I read you can also install taller 3 litre gears (1.62, 1.76) if you remove the bushing under the bearing on the front gear, install the correct bearing/race, figure out how to machine, or shim it all up. I think it was Capt.Insane-O that did this. He couldn't remember the exact details and said it was a pain, but possible.
I know I'm off subject again.

**racervboat** · 02-28-2024, 01:31 PM

The newer case one's with the rear rectangle anode can be small and big bearing.1647-9147,c,c1 is big bearing ratching,c2,c3,c4 non ratcheting.1647-9148 all small bearing.

All the guts from either big or small can be swapped out.

**OnPad** · 02-28-2024, 01:36 PM

So your saying that either gear can be used. Do you have to remove a bushing on the forward gear? Bearing and race need to be changed out?

**racervboat** · 02-28-2024, 01:50 PM

Im saying big bearing non ratchet to big bearing ratchet or vice versa.

Same with small bearing.

You cannot put big into small or vice versa.

**OnPad** · 02-28-2024, 02:00 PM

I guess I didn't know they made a big bearing non ratchet, or a small bearing ratchet fishing case.

**NZ Sidewinder** · 02-28-2024, 02:06 PM

Just to complicate things a little.
This box is now ready to paint but it wasn't all plain sailing.
The forward gear went in with a .015 shim first off which put the backlash at .030 which is a little rattley.
So I put .022 shims in and that sorted that.
.022 is a realistic shim so there was no reason to suspect anything was wrong with the gearset.
Pinion height was .025.
Then when I tightened the carrier nut there was a tight spot on the reverse gear.
I played around with this for a bit but it was clear that something was wrong.
Then I compared the new reverse gear to a used one and it was different.
It was thicker and had a slightly different fit depth on the reverse bearing.
So I used an older use reverse gear and the tight spot disappeared.
I know it was an issue with a gear and not a pinion because the tight spot was a every 1.87 turns of the drive shaft.

**racervboat** · 02-28-2024, 02:06 PM

I got a big bearing non ratchet in my garage now.With the newer case small i do not think they made a ratcheting but an older small bearing ratcheting gear set will swap into it. Damn mercury chit can get confusing that's for sure.

**racervboat** · 02-28-2024, 02:08 PM

Originally Posted by NZ Sidewinder

Just to complicate things a little.
This box is now ready to paint but it wasn't all plain sailing.
The forward gear went in with a .015 shim first off which put the backlash at .030 which is a little rattley.
So I put .022 shims in and that sorted that.
.022 is a realistic shim so there was no reason to suspect anything was wrong with the gearset.
Pinion height was .025.
Then when I tightened the carrier nut there was a tight spot on the reverse gear.
I played around with this for a bit but it was clear that something was wrong.
Then I compared the new reverse gear to a used one and it was different.
It was thicker and had a slightly different fit depth on the reverse bearing.
So I used an older use reverse gear and the tight spot disappeared.
I know it was an issue with a gear and not a pinion because the tight spot was a every 1.87 turns of the drive shaft.

I have ran into that before too.

**OnPad** · 02-28-2024, 02:22 PM

You guys might of just saved me a headache in the future. Thanks!

**rjdubiel** · 02-28-2024, 02:38 PM

Originally Posted by OnPad

You guys might of just saved me a headache in the future. Thanks!

They usually do! All knowing knowledge is here if you have the time to find it. It is amazing how much you can find here if you use Google for the search and know how to use Google to find here. in the address bar type in what your looking for and put "Screamandfly.com" behind your search phrase and you will have all threads, even archive posts.